Well, so I eventually lost my learner rank.
I think the problem might be caused by me changing the IGN or the server 1.8 update.
For more details:
My old IGN: fly_snow / SFrost_now (Cuz I changed it twice)
My IGN right now: Cirrostratus
Admin, please help if you can. Ill be appreciate for that. Thank you.
I just checked it. It seems to be fixed.